Gemstone



FIG. 1 is a top plan view showing my new design;

FIG. 2 is a front elevation view thereof, the rear elevation view being a mirror image;

FIG. 3 is a right side elevation view thereof, the left side elevation view being a mirror image;

FIG. 4 is a bottom, front and top perspective view thereof; and,

FIG. 5 is a top, front and bottom perspective view thereof. 

The ornamental design for a gemstone, as shown and described. 